#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>

int main()
{
	printf("I am running...\n");
	pid_t id = fork();
	if (id == 0) { // child process
		int count = 5;
		while (count) {
			printf("I am child process......PID:%d, PPID:%d, count:%d\n", getpid(), getppid(), count);
			sleep(1);
			count--;
		}
		printf("child process quit\n");
		exit(0);
	}
	else if (id > 0) { // father process
		while (1) {
			printf("I am father process.....PID:%d, PPID:%d\n", getpid(), getppid());
			sleep(1);
		}
	}
	else { // fork error

	}
	return 0;
} 